Tektronix 321A Instruction Manual page 5

Type 321A
SECTION
I
CHARACTERISTICS
lntrodudion
The Tektronix Type 321A is a high-performance, dc-to-6
me, transistorized oscilloscope. Its light weight, small size
and ability to operate from o variety of power sources make
it a versatile field and laboratory instrument. The oscillo-
scope con operate from its internally-contained rechargeable
battery pock, on external de source or from o 115/ 230-volt
50-800 cycle ac line. Regulated power supplies in the instru-
ment, a ccurate calibration, and precise linearity assure exact
time and amplitude measurements despite normal voltage-
source and power-supply-load changes that occur under
odual operating conditions.
Operating temperature range derived from tests indicates
optimum performance and reliability on its self-contained
batteries from
o·
to + 40°
c
ot altitudes up to 15,000 feet .
Temperature range without batteries when operating from on
external source is
- 15 •
C to +55 • C. Non-operating tem-
perature range is -55" C to +75" C without batteries
and
-40•
C to
+ 60"
C with batteries at altitudes to
50,000
feet.
For
the operator's convenience, a front-panel battery lighl
indicates when the internal batteries o re low.
If
external de
or a c operation is being used instead of the batteries, the
light turns on if the external voltage source drops too low
for proper power supply regulation.
A 4-position power switch on the front panel permits
convenient selection of charging rote and /or power source.
Vertical Deflection System
Bandpass- De to at least
6
me (3-db down) using de cou-
pling; using oc coupling, low-frequency 3-db down poinl
is
2
cps typical from a 1-kc reference.
Sensitivity-0.01 v/div to 20 v/div in
11 calibrated steps;
occurocy is within
3"/o
of front -panel markings. Con-
tinuously variable from 0.01 v/div to about 50 v/div
uncolibroted.
Input lmpedance-35 pf nomina l paralleled by 1 megohm
(:.t
1 "/o), 8.2
pf nominal paralleled by
10
megohms
(±2%1 when using the P6006
lO X
Probe.
Maximum Allowable Input Voltage Roting-600 volts com-
bined de and peak oc; 600 volts (not 1200 volts) peak-to-
peak oc.
Triggering
Type-Automatic, or amplitude-level selection using pre-
set stability.
Modo-Ac-coupled or De-coupled.
Slope-Plus, from rising slope of triggering waveform, or
minus from negative slope of triggering waveform.
Source- Internal from vertical signal, or external from
triggering signal.
Signal Requirements- Internal: 0.2 major division vertical
deflection a t
1 kc increasing to 1 major division
at
6
me.
External: 1 volt peok-to-peak at l kc increasing to 3 volts
peak-to-peak at
6
me. Nominal input impedance: 5 pf
paralleled by 100 kilohms (± 20%).
Sweep
Type- Miller Integrator.
Sweep Rotes-0.5JLsec/div to O.S sei:/div in 19 calibrated
steps. Accurate 5X sweep magnifier extends calibrated
range to 0.1 p.sec/div. Calibrated sweep-rote accuracy
is :t:3"/o. Sweep time adjustable between steps and to
~
1.5 sec/div uncolibrated.
External Horizontal Input
Bandpass-De to at least
1
me (3-db down).
Deflection Foetor-! vfdv + 10"/o with 5 X magnifier an.
Input lmpedanc&-30 pf typical paralleled by 100 kilohms
1± 5% ).
Amplitude Calibrator
Square Wove-Frequency about
2
kc.
Amplitude-500 mv peak-to-peak. Also
40
mv peok-to·
peak internally coupled in CAL4 DIV position of VOLTS/
DIV switch. Peak-to-peok amplitude a ccuracy is ± 3%.
Cathode-Ray Tube
Type-Special Tektronix-manufactured 13211 . 3" flat-face,
post-deflection accelerator. l ow healer power.
Accelerating Potcntiol-4 kv.
Z-Axis Modulation- External terminal permits RC coupling
to crt grid.
Unblonking-Deflection unblanking.
Phosphor- Type
P31
normally furnished;
PI, P2,
P7, and
Pl l
phosphors optional. Other phosphors furnished on
special order.
Graticule
Illumination- Variable edge lighting when operating from
ac line.
Display Area- Marked In 6-vertical and 1 0-horizontol
1 /
4 "
divisions.
Power Requirements
Source-Operates from I 0 size D flashlight cells, or 10
size D rechargeable cells (approximately 3 hours using
2.5 ampere-hour cells; approximately 5 hours using
4
1-1